Hex #407e75 or rgb(64,126,117) in RGB space is the tint of greenish cian. It has hue angle of 171.29 degrees, value = 49 and saturation = 49. #407e75 can be obtained by mixing 4 colors: 1 drop of magenta, 3 drops of blue, 3 drops of green, 1 drop of white.
Nearest safe hex - #336666. Below you can see the block with #407e75 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #407e75 to the mixer and play with it.